| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * Virtio SCSI HBA driver |
| * |
| * Copyright IBM Corp. 2010 |
| * Copyright Red Hat, Inc. 2011 |
| * |
| * Authors: |
| * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> |
| * Paolo Bonzini <pbonzini@redhat.com> |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/module.h> |
| #include <linux/slab.h> |
| #include <linux/mempool.h> |
| #include <linux/interrupt.h> |
| #include <linux/virtio.h> |
| #include <linux/virtio_ids.h> |
| #include <linux/virtio_config.h> |
| #include <linux/virtio_scsi.h> |
| #include <linux/cpu.h> |
| #include <linux/blkdev.h> |
| #include <scsi/scsi_host.h> |
| #include <scsi/scsi_device.h> |
| #include <scsi/scsi_cmnd.h> |
| #include <scsi/scsi_tcq.h> |
| #include <scsi/scsi_devinfo.h> |
| #include <linux/seqlock.h> |
| #include <linux/blk-mq-virtio.h> |
| |
| #include "sd.h" |
| |
| #define VIRTIO_SCSI_MEMPOOL_SZ 64 |
| #define VIRTIO_SCSI_EVENT_LEN 8 |
| #define VIRTIO_SCSI_VQ_BASE 2 |
| |
| /* Command queue element */ |
| struct virtio_scsi_cmd { |
| struct scsi_cmnd *sc; |
| struct completion *comp; |
| union { |
| struct virtio_scsi_cmd_req cmd; |
| struct virtio_scsi_cmd_req_pi cmd_pi; |
| struct virtio_scsi_ctrl_tmf_req tmf; |
| struct virtio_scsi_ctrl_an_req an; |
| } req; |
| union { |
| struct virtio_scsi_cmd_resp cmd; |
| struct virtio_scsi_ctrl_tmf_resp tmf; |
| struct virtio_scsi_ctrl_an_resp an; |
| struct virtio_scsi_event evt; |
| } resp; |
| } ____cacheline_aligned_in_smp; |
| |
| struct virtio_scsi_event_node { |
| struct virtio_scsi *vscsi; |
| struct virtio_scsi_event event; |
| struct work_struct work; |
| }; |
| |
| struct virtio_scsi_vq { |
| /* Protects vq */ |
| spinlock_t vq_lock; |
| |
| struct virtqueue *vq; |
| }; |
| |
| /* Driver instance state */ |
| struct virtio_scsi { |
| struct virtio_device *vdev; |
| |
| /* Get some buffers ready for event vq */ |
| struct virtio_scsi_event_node event_list[VIRTIO_SCSI_EVENT_LEN]; |
| |
| u32 num_queues; |
| |
| struct hlist_node node; |
| |
| /* Protected by event_vq lock */ |
| bool stop_events; |
| |
| struct virtio_scsi_vq ctrl_vq; |
| struct virtio_scsi_vq event_vq; |
| struct virtio_scsi_vq req_vqs[]; |
| }; |
| |
| static struct kmem_cache *virtscsi_cmd_cache; |
| static mempool_t *virtscsi_cmd_pool; |
| |
| static inline struct Scsi_Host *virtio_scsi_host(struct virtio_device *vdev) |
| { |
| return vdev->priv; |
| } |
| |
| static void virtscsi_compute_resid(struct scsi_cmnd *sc, u32 resid) |
| { |
| if (resid) |
| scsi_set_resid(sc, resid); |
| } |
| |
| /* |
| * virtscsi_complete_cmd - finish a scsi_cmd and invoke scsi_done |
| * |
| * Called with vq_lock held. |
| */ |
| static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf) |
| { |
| struct virtio_scsi_cmd *cmd = buf; |
| struct scsi_cmnd *sc = cmd->sc; |
| struct virtio_scsi_cmd_resp *resp = &cmd->resp.cmd; |
| |
| dev_dbg(&sc->device->sdev_gendev, |
| "cmd %p response %u status %#02x sense_len %u\n", |
| sc, resp->response, resp->status, resp->sense_len); |
| |
| sc->result = resp->status; |
| virtscsi_compute_resid(sc, virtio32_to_cpu(vscsi->vdev, resp->resid)); |
| switch (resp->response) { |
| case VIRTIO_SCSI_S_OK: |
| set_host_byte(sc, DID_OK); |
| break; |
| case VIRTIO_SCSI_S_OVERRUN: |
| set_host_byte(sc, DID_ERROR); |
| break; |
| case VIRTIO_SCSI_S_ABORTED: |
| set_host_byte(sc, DID_ABORT); |
| break; |
| case VIRTIO_SCSI_S_BAD_TARGET: |
| set_host_byte(sc, DID_BAD_TARGET); |
| break; |
| case VIRTIO_SCSI_S_RESET: |
| set_host_byte(sc, DID_RESET); |
| break; |
| case VIRTIO_SCSI_S_BUSY: |
| set_host_byte(sc, DID_BUS_BUSY); |
| break; |
| case VIRTIO_SCSI_S_TRANSPORT_FAILURE: |
| set_host_byte(sc, DID_TRANSPORT_DISRUPTED); |
| break; |
| case VIRTIO_SCSI_S_TARGET_FAILURE: |
| set_host_byte(sc, DID_TARGET_FAILURE); |
| break; |
| case VIRTIO_SCSI_S_NEXUS_FAILURE: |
| set_host_byte(sc, DID_NEXUS_FAILURE); |
| break; |
| default: |
| scmd_printk(KERN_WARNING, sc, "Unknown response %d", |
| resp->response); |
| /* fall through */ |
| case VIRTIO_SCSI_S_FAILURE: |
| set_host_byte(sc, DID_ERROR); |
| break; |
| } |
| |
| WARN_ON(virtio32_to_cpu(vscsi->vdev, resp->sense_len) > |
| VIRTIO_SCSI_SENSE_SIZE); |
| if (sc->sense_buffer) { |
| memcpy(sc->sense_buffer, resp->sense, |
| min_t(u32, |
| virtio32_to_cpu(vscsi->vdev, resp->sense_len), |
| VIRTIO_SCSI_SENSE_SIZE)); |
| if (resp->sense_len) |
| set_driver_byte(sc, DRIVER_SENSE); |
| } |
| |
| sc->scsi_done(sc); |
| } |
| |
| static void virtscsi_vq_done(struct virtio_scsi *vscsi, |
| struct virtio_scsi_vq *virtscsi_vq, |
| void (*fn)(struct virtio_scsi *vscsi, void *buf)) |
| { |
| void *buf; |
| unsigned int len; |
| unsigned long flags; |
| struct virtqueue *vq = virtscsi_vq->vq; |
| |
| spin_lock_irqsave(&virtscsi_vq->vq_lock, flags); |
| do { |
| virtqueue_disable_cb(vq); |
| while ((buf = virtqueue_get_buf(vq, &len)) != NULL) |
| fn(vscsi, buf); |
| |
| if (unlikely(virtqueue_is_broken(vq))) |
| break; |
| } while (!virtqueue_enable_cb(vq)); |
| spin_unlock_irqrestore(&virtscsi_vq->vq_lock, flags); |
| } |
| |
| static void virtscsi_req_done(struct virtqueue *vq) |
| { |
| struct Scsi_Host *sh = virtio_scsi_host(vq->vdev); |
| struct virtio_scsi *vscsi = shost_priv(sh); |
| int index = vq->index - VIRTIO_SCSI_VQ_BASE; |
| struct virtio_scsi_vq *req_vq = &vscsi->req_vqs[index]; |
| |
| virtscsi_vq_done(vscsi, req_vq, virtscsi_complete_cmd); |
| }; |
| |
| static void virtscsi_poll_requests(struct virtio_scsi *vscsi) |
| { |
| int i, num_vqs; |
| |
| num_vqs = vscsi->num_queues; |
| for (i = 0; i < num_vqs; i++) |
| virtscsi_vq_done(vscsi, &vscsi->req_vqs[i], |
| virtscsi_complete_cmd); |
| } |
| |
| static void virtscsi_complete_free(struct virtio_scsi *vscsi, void *buf) |
| { |
| struct virtio_scsi_cmd *cmd = buf; |
| |
| if (cmd->comp) |
| complete(cmd->comp); |
| } |
| |
| static void virtscsi_ctrl_done(struct virtqueue *vq) |
| { |
| struct Scsi_Host *sh = virtio_scsi_host(vq->vdev); |
| struct virtio_scsi *vscsi = shost_priv(sh); |
| |
| virtscsi_vq_done(vscsi, &vscsi->ctrl_vq, virtscsi_complete_free); |
| }; |
| |
| static void virtscsi_handle_event(struct work_struct *work); |
| |
| static int virtscsi_kick_event(struct virtio_scsi *vscsi, |
| struct virtio_scsi_event_node *event_node) |
| { |
| int err; |
| struct scatterlist sg; |
| unsigned long flags; |
| |
| INIT_WORK(&event_node->work, virtscsi_handle_event); |
| sg_init_one(&sg, &event_node->event, sizeof(struct virtio_scsi_event)); |
| |
| spin_lock_irqsave(&vscsi->event_vq.vq_lock, flags); |
| |
| err = virtqueue_add_inbuf(vscsi->event_vq.vq, &sg, 1, event_node, |
| GFP_ATOMIC); |
| if (!err) |
| virtqueue_kick(vscsi->event_vq.vq); |
| |
| spin_unlock_irqrestore(&vscsi->event_vq.vq_lock, flags); |
| |
| return err; |
| } |
| |
| static int virtscsi_kick_event_all(struct virtio_scsi *vscsi) |
| { |
| int i; |
| |
| for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++) { |
| vscsi->event_list[i].vscsi = vscsi; |
| virtscsi_kick_event(vscsi, &vscsi->event_list[i]); |
| } |
| |
| return 0; |
| } |
| |
| static void virtscsi_cancel_event_work(struct virtio_scsi *vscsi) |
| { |
| int i; |
| |
| /* Stop scheduling work before calling cancel_work_sync. */ |
| spin_lock_irq(&vscsi->event_vq.vq_lock); |
| vscsi->stop_events = true; |
| spin_unlock_irq(&vscsi->event_vq.vq_lock); |
| |
| for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++) |
| cancel_work_sync(&vscsi->event_list[i].work); |
| } |
| |
| static void virtscsi_handle_transport_reset(struct virtio_scsi *vscsi, |
| struct virtio_scsi_event *event) |
| { |
| struct scsi_device *sdev; |
| struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev); |
| unsigned int target = event->lun[1]; |
| unsigned int lun = (event->lun[2] << 8) | event->lun[3]; |
| |
| switch (virtio32_to_cpu(vscsi->vdev, event->reason)) { |
| case VIRTIO_SCSI_EVT_RESET_RESCAN: |
| scsi_add_device(shost, 0, target, lun); |
| break; |
| case VIRTIO_SCSI_EVT_RESET_REMOVED: |
| sdev = scsi_device_lookup(shost, 0, target, lun); |
| if (sdev) { |
| scsi_remove_device(sdev); |
| scsi_device_put(sdev); |
| } else { |
| pr_err("SCSI device %d 0 %d %d not found\n", |
| shost->host_no, target, lun); |
| } |
| break; |
| default: |
| pr_info("Unsupport virtio scsi event reason %x\n", event->reason); |
| } |
| } |
| |
| static void virtscsi_handle_param_change(struct virtio_scsi *vscsi, |
| struct virtio_scsi_event *event) |
| { |
| struct scsi_device *sdev; |
| struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev); |
| unsigned int target = event->lun[1]; |
| unsigned int lun = (event->lun[2] << 8) | event->lun[3]; |
| u8 asc = virtio32_to_cpu(vscsi->vdev, event->reason) & 255; |
| u8 ascq = virtio32_to_cpu(vscsi->vdev, event->reason) >> 8; |
| |
| sdev = scsi_device_lookup(shost, 0, target, lun); |
| if (!sdev) { |
| pr_err("SCSI device %d 0 %d %d not found\n", |
| shost->host_no, target, lun); |
| return; |
| } |
| |
| /* Handle "Parameters changed", "Mode parameters changed", and |
| "Capacity data has changed". */ |
| if (asc == 0x2a && (ascq == 0x00 || ascq == 0x01 || ascq == 0x09)) |
| scsi_rescan_device(&sdev->sdev_gendev); |
| |
| scsi_device_put(sdev); |
| } |
| |
| static void virtscsi_rescan_hotunplug(struct virtio_scsi *vscsi) |
| { |
| struct scsi_device *sdev; |
| struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev); |
| unsigned char scsi_cmd[MAX_COMMAND_SIZE]; |
| int result, inquiry_len, inq_result_len = 256; |
| char *inq_result = kmalloc(inq_result_len, GFP_KERNEL); |
| |
| shost_for_each_device(sdev, shost) { |
| inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36; |
| |
| memset(scsi_cmd, 0, sizeof(scsi_cmd)); |
| scsi_cmd[0] = INQUIRY; |
| scsi_cmd[4] = (unsigned char) inquiry_len; |
| |
| memset(inq_result, 0, inq_result_len); |
| |
| result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, |
| inq_result, inquiry_len, NULL, |
| SD_TIMEOUT, SD_MAX_RETRIES, NULL); |
| |
| if (result == 0 && inq_result[0] >> 5) { |
| /* PQ indicates the LUN is not attached */ |
| scsi_remove_device(sdev); |
| } else if (host_byte(result) == DID_BAD_TARGET) { |
| /* |
| * If all LUNs of a virtio-scsi device are unplugged |
| * it will respond with BAD TARGET on any INQUIRY |
| * command. |
| * Remove the device in this case as well. |
| */ |
| scsi_remove_device(sdev); |
| } |
| } |
| |
| kfree(inq_result); |
| } |
| |
| static void virtscsi_handle_event(struct work_struct *work) |
| { |
| struct virtio_scsi_event_node *event_node = |
| container_of(work, struct virtio_scsi_event_node, work); |
| struct virtio_scsi *vscsi = event_node->vscsi; |
| struct virtio_scsi_event *event = &event_node->event; |
| |
| if (event->event & |
| cpu_to_virtio32(vscsi->vdev, VIRTIO_SCSI_T_EVENTS_MISSED)) { |
| event->event &= ~cpu_to_virtio32(vscsi->vdev, |
| VIRTIO_SCSI_T_EVENTS_MISSED); |
| virtscsi_rescan_hotunplug(vscsi); |
| scsi_scan_host(virtio_scsi_host(vscsi->vdev)); |
| } |
| |
| switch (virtio32_to_cpu(vscsi->vdev, event->event)) { |
| case VIRTIO_SCSI_T_NO_EVENT: |
| break; |
| case VIRTIO_SCSI_T_TRANSPORT_RESET: |
| virtscsi_handle_transport_reset(vscsi, event); |
| break; |
| case VIRTIO_SCSI_T_PARAM_CHANGE: |
| virtscsi_handle_param_change(vscsi, event); |
| break; |
| default: |
| pr_err("Unsupport virtio scsi event %x\n", event->event); |
| } |
| virtscsi_kick_event(vscsi, event_node); |
| } |
| |
| static void virtscsi_complete_event(struct virtio_scsi *vscsi, void *buf) |
| { |
| struct virtio_scsi_event_node *event_node = buf; |
| |
| if (!vscsi->stop_events) |
| queue_work(system_freezable_wq, &event_node->work); |
| } |
| |
| static void virtscsi_event_done(struct virtqueue *vq) |
| { |
| struct Scsi_Host *sh = virtio_scsi_host(vq->vdev); |
| struct virtio_scsi *vscsi = shost_priv(sh); |
| |
| virtscsi_vq_done(vscsi, &vscsi->event_vq, virtscsi_complete_event); |
| }; |
| |
| static int __virtscsi_add_cmd(struct virtqueue *vq, |
| struct virtio_scsi_cmd *cmd, |
| size_t req_size, size_t resp_size) |
| { |
| struct scsi_cmnd *sc = cmd->sc; |
| struct scatterlist *sgs[6], req, resp; |
| struct sg_table *out, *in; |
| unsigned out_num = 0, in_num = 0; |
| |
| out = in = NULL; |
| |
| if (sc && sc->sc_data_direction != DMA_NONE) { |
| if (sc->sc_data_direction != DMA_FROM_DEVICE) |
| out = &sc->sdb.table; |
| if (sc->sc_data_direction != DMA_TO_DEVICE) |
| in = &sc->sdb.table; |
| } |
| |
| /* Request header. */ |
| sg_init_one(&req, &cmd->req, req_size); |
| sgs[out_num++] = &req; |
| |
| /* Data-out buffer. */ |
| if (out) { |
| /* Place WRITE protection SGLs before Data OUT payload */ |
| if (scsi_prot_sg_count(sc)) |
| sgs[out_num++] = scsi_prot_sglist(sc); |
| sgs[out_num++] = out->sgl; |
| } |
| |
| /* Response header. */ |
| sg_init_one(&resp, &cmd->resp, resp_size); |
| sgs[out_num + in_num++] = &resp; |
| |
| /* Data-in buffer */ |
| if (in) { |
| /* Place READ protection SGLs before Data IN payload */ |
| if (scsi_prot_sg_count(sc)) |
| sgs[out_num + in_num++] = scsi_prot_sglist(sc); |
| sgs[out_num + in_num++] = in->sgl; |
| } |
| |
| return virtqueue_add_sgs(vq, sgs, out_num, in_num, cmd, GFP_ATOMIC); |
| } |
| |
| static void virtscsi_kick_vq(struct virtio_scsi_vq *vq) |
| { |
| bool needs_kick; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&vq->vq_lock, flags); |
| needs_kick = virtqueue_kick_prepare(vq->vq); |
| spin_unlock_irqrestore(&vq->vq_lock, flags); |
| |
| if (needs_kick) |
| virtqueue_notify(vq->vq); |
| } |
| |
| /** |
| * virtscsi_add_cmd - add a virtio_scsi_cmd to a virtqueue, optionally kick it |
| * @vq : the struct virtqueue we're talking about |
| * @cmd : command structure |
| * @req_size : size of the request buffer |
| * @resp_size : size of the response buffer |
| * @kick : whether to kick the virtqueue immediately |
| */ |
| static int virtscsi_add_cmd(struct virtio_scsi_vq *vq, |
| struct virtio_scsi_cmd *cmd, |
| size_t req_size, size_t resp_size, |
| bool kick) |
| { |
| unsigned long flags; |
| int err; |
| bool needs_kick = false; |
| |
| spin_lock_irqsave(&vq->vq_lock, flags); |
| err = __virtscsi_add_cmd(vq->vq, cmd, req_size, resp_size); |
| if (!err && kick) |
| needs_kick = virtqueue_kick_prepare(vq->vq); |
| |
| spin_unlock_irqrestore(&vq->vq_lock, flags); |
| |
| if (needs_kick) |
| virtqueue_notify(vq->vq); |
| return err; |
| } |
| |
| static void virtio_scsi_init_hdr(struct virtio_device *vdev, |
| struct virtio_scsi_cmd_req *cmd, |
| struct scsi_cmnd *sc) |
| { |
| cmd->lun[0] = 1; |
| cmd->lun[1] = sc->device->id; |
| cmd->lun[2] = (sc->device->lun >> 8) | 0x40; |
| cmd->lun[3] = sc->device->lun & 0xff; |
| cmd->tag = cpu_to_virtio64(vdev, (unsigned long)sc); |
| cmd->task_attr = VIRTIO_SCSI_S_SIMPLE; |
| cmd->prio = 0; |
| cmd->crn = 0; |
| } |
| |
| #ifdef CONFIG_BLK_DEV_INTEGRITY |
| static void virtio_scsi_init_hdr_pi(struct virtio_device *vdev, |
| struct virtio_scsi_cmd_req_pi *cmd_pi, |
| struct scsi_cmnd *sc) |
| { |
| struct request *rq = sc->request; |
| struct blk_integrity *bi; |
| |
| virtio_scsi_init_hdr(vdev, (struct virtio_scsi_cmd_req *)cmd_pi, sc); |
| |
| if (!rq || !scsi_prot_sg_count(sc)) |
| return; |
| |
| bi = blk_get_integrity(rq->rq_disk); |
| |
| if (sc->sc_data_direction == DMA_TO_DEVICE) |
| cmd_pi->pi_bytesout = cpu_to_virtio32(vdev, |
| bio_integrity_bytes(bi, |
| blk_rq_sectors(rq))); |
| else if (sc->sc_data_direction == DMA_FROM_DEVICE) |
| cmd_pi->pi_bytesin = cpu_to_virtio32(vdev, |
| bio_integrity_bytes(bi, |
| blk_rq_sectors(rq))); |
| } |
| #endif |
| |
| static struct virtio_scsi_vq *virtscsi_pick_vq_mq(struct virtio_scsi *vscsi, |
| struct scsi_cmnd *sc) |
| { |
| u32 tag = blk_mq_unique_tag(sc->request); |
| u16 hwq = blk_mq_unique_tag_to_hwq(tag); |
| |
| return &vscsi->req_vqs[hwq]; |
| } |
| |
| static int virtscsi_queuecommand(struct Scsi_Host *shost, |
| struct scsi_cmnd *sc) |
| { |
| struct virtio_scsi *vscsi = shost_priv(shost); |
| struct virtio_scsi_vq *req_vq = virtscsi_pick_vq_mq(vscsi, sc); |
| struct virtio_scsi_cmd *cmd = scsi_cmd_priv(sc); |
| bool kick; |
| unsigned long flags; |
| int req_size; |
| int ret; |
| |
| BUG_ON(scsi_sg_count(sc) > shost->sg_tablesize); |
| |
| /* TODO: check feature bit and fail if unsupported? */ |
| BUG_ON(sc->sc_data_direction == DMA_BIDIRECTIONAL); |
| |
| dev_dbg(&sc->device->sdev_gendev, |
| "cmd %p CDB: %#02x\n", sc, sc->cmnd[0]); |
| |
| cmd->sc = sc; |
| |
| BUG_ON(sc->cmd_len > VIRTIO_SCSI_CDB_SIZE); |
| |
| #ifdef CONFIG_BLK_DEV_INTEGRITY |
| if (virtio_has_feature(vscsi->vdev, VIRTIO_SCSI_F_T10_PI)) { |
| virtio_scsi_init_hdr_pi(vscsi->vdev, &cmd->req.cmd_pi, sc); |
| memcpy(cmd->req.cmd_pi.cdb, sc->cmnd, sc->cmd_len); |
| req_size = sizeof(cmd->req.cmd_pi); |
| } else |
| #endif |
| { |
| virtio_scsi_init_hdr(vscsi->vdev, &cmd->req.cmd, sc); |
| memcpy(cmd->req.cmd.cdb, sc->cmnd, sc->cmd_len); |
| req_size = sizeof(cmd->req.cmd); |
| } |
| |
| kick = (sc->flags & SCMD_LAST) != 0; |
| ret = virtscsi_add_cmd(req_vq, cmd, req_size, sizeof(cmd->resp.cmd), kick); |
| if (ret == -EIO) { |
| cmd->resp.cmd.response = VIRTIO_SCSI_S_BAD_TARGET; |
| spin_lock_irqsave(&req_vq->vq_lock, flags); |
| virtscsi_complete_cmd(vscsi, cmd); |
| spin_unlock_irqrestore(&req_vq->vq_lock, flags); |
| } else if (ret != 0) { |
| return SCSI_MLQUEUE_HOST_BUSY; |
| } |
| return 0; |
| } |
| |
| static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd) |
| { |
| DECLARE_COMPLETION_ONSTACK(comp); |
| int ret = FAILED; |
| |
| cmd->comp = ∁ |
| if (virtscsi_add_cmd(&vscsi->ctrl_vq, cmd, |
| sizeof cmd->req.tmf, sizeof cmd->resp.tmf, true) < 0) |
| goto out; |
| |
| wait_for_completion(&comp); |
| if (cmd->resp.tmf.response == VIRTIO_SCSI_S_OK || |
| cmd->resp.tmf.response == VIRTIO_SCSI_S_FUNCTION_SUCCEEDED) |
| ret = SUCCESS; |
| |
| /* |
| * The spec guarantees that all requests related to the TMF have |
| * been completed, but the callback might not have run yet if |
| * we're using independent interrupts (e.g. MSI). Poll the |
| * virtqueues once. |
| * |
| * In the abort case, sc->scsi_done will do nothing, because |
| * the block layer must have detected a timeout and as a result |
| * REQ_ATOM_COMPLETE has been set. |
| */ |
| virtscsi_poll_requests(vscsi); |
| |
| out: |
| mempool_free(cmd, virtscsi_cmd_pool); |
| return ret; |
| } |
| |
| static int virtscsi_device_reset(struct scsi_cmnd *sc) |
| { |
| struct virtio_scsi *vscsi = shost_priv(sc->device->host); |
| struct virtio_scsi_cmd *cmd; |
| |
| sdev_printk(KERN_INFO, sc->device, "device reset\n"); |
| cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO); |
| if (!cmd) |
| return FAILED; |
| |
| memset(cmd, 0, sizeof(*cmd)); |
| cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){ |
| .type = VIRTIO_SCSI_T_TMF, |
| .subtype = cpu_to_virtio32(vscsi->vdev, |
| VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET), |
| .lun[0] = 1, |
| .lun[1] = sc->device->id, |
| .lun[2] = (sc->device->lun >> 8) | 0x40, |
| .lun[3] = sc->device->lun & 0xff, |
| }; |
| return virtscsi_tmf(vscsi, cmd); |
| } |
| |
| static int virtscsi_device_alloc(struct scsi_device *sdevice) |
| { |
| /* |
| * Passed through SCSI targets (e.g. with qemu's 'scsi-block') |
| * may have transfer limits which come from the host SCSI |
| * controller or something on the host side other than the |
| * target itself. |
| * |
| * To make this work properly, the hypervisor can adjust the |
| * target's VPD information to advertise these limits. But |
| * for that to work, the guest has to look at the VPD pages, |
| * which we won't do by default if it is an SPC-2 device, even |
| * if it does actually support it. |
| * |
| * So, set the blist to always try to read the VPD pages. |
| */ |
| sdevice->sdev_bflags = BLIST_TRY_VPD_PAGES; |
| |
| return 0; |
| } |
| |
| |
| /** |
| * virtscsi_change_queue_depth() - Change a virtscsi target's queue depth |
| * @sdev: Virtscsi target whose queue depth to change |
| * @qdepth: New queue depth |
| */ |
| static int virtscsi_change_queue_depth(struct scsi_device *sdev, int qdepth) |
| { |
| struct Scsi_Host *shost = sdev->host; |
| int max_depth = shost->cmd_per_lun; |
| |
| return scsi_change_queue_depth(sdev, min(max_depth, qdepth)); |
| } |
| |
| static int virtscsi_abort(struct scsi_cmnd *sc) |
| { |
| struct virtio_scsi *vscsi = shost_priv(sc->device->host); |
| struct virtio_scsi_cmd *cmd; |
| |
| scmd_printk(KERN_INFO, sc, "abort\n"); |
| cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO); |
| if (!cmd) |
| return FAILED; |
| |
| memset(cmd, 0, sizeof(*cmd)); |
| cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){ |
| .type = VIRTIO_SCSI_T_TMF, |
| .subtype = VIRTIO_SCSI_T_TMF_ABORT_TASK, |
| .lun[0] = 1, |
| .lun[1] = sc->device->id, |
| .lun[2] = (sc->device->lun >> 8) | 0x40, |
| .lun[3] = sc->device->lun & 0xff, |
| .tag = cpu_to_virtio64(vscsi->vdev, (unsigned long)sc), |
| }; |
| return virtscsi_tmf(vscsi, cmd); |
| } |
| |
| static int virtscsi_map_queues(struct Scsi_Host *shost) |
| { |
| struct virtio_scsi *vscsi = shost_priv(shost); |
| struct blk_mq_queue_map *qmap = &shost->tag_set.map[HCTX_TYPE_DEFAULT]; |
| |
| return blk_mq_virtio_map_queues(qmap, vscsi->vdev, 2); |
| } |
| |
| static void virtscsi_commit_rqs(struct Scsi_Host *shost, u16 hwq) |
| { |
| struct virtio_scsi *vscsi = shost_priv(shost); |
| |
| virtscsi_kick_vq(&vscsi->req_vqs[hwq]); |
| } |
| |
| /* |
| * The host guarantees to respond to each command, although I/O |
| * latencies might be higher than on bare metal. Reset the timer |
| * unconditionally to give the host a chance to perform EH. |
| */ |
| static enum blk_eh_timer_return virtscsi_eh_timed_out(struct scsi_cmnd *scmnd) |
| { |
| return BLK_EH_RESET_TIMER; |
| } |
| |
| static struct scsi_host_template virtscsi_host_template = { |
| .module = THIS_MODULE, |
| .name = "Virtio SCSI HBA", |
| .proc_name = "virtio_scsi", |
| .this_id = -1, |
| .cmd_size = sizeof(struct virtio_scsi_cmd), |
| .queuecommand = virtscsi_queuecommand, |
| .commit_rqs = virtscsi_commit_rqs, |
| .change_queue_depth = virtscsi_change_queue_depth, |
| .eh_abort_handler = virtscsi_abort, |
| .eh_device_reset_handler = virtscsi_device_reset, |
| .eh_timed_out = virtscsi_eh_timed_out, |
| .slave_alloc = virtscsi_device_alloc, |
| |
| .dma_boundary = UINT_MAX, |
| .map_queues = virtscsi_map_queues, |
| .track_queue_depth = 1, |
| }; |
| |
| #define virtscsi_config_get(vdev, fld) \ |
| ({ \ |
| __virtio_native_type(struct virtio_scsi_config, fld) __val; \ |
| virtio_cread(vdev, struct virtio_scsi_config, fld, &__val); \ |
| __val; \ |
| }) |
| |
| #define virtscsi_config_set(vdev, fld, val) \ |
| do { \ |
| __virtio_native_type(struct virtio_scsi_config, fld) __val = (val); \ |
| virtio_cwrite(vdev, struct virtio_scsi_config, fld, &__val); \ |
| } while(0) |
| |
| static void virtscsi_init_vq(struct virtio_scsi_vq *virtscsi_vq, |
| struct virtqueue *vq) |
| { |
| spin_lock_init(&virtscsi_vq->vq_lock); |
| virtscsi_vq->vq = vq; |
| } |
| |
| static void virtscsi_remove_vqs(struct virtio_device *vdev) |
| { |
| /* Stop all the virtqueues. */ |
| vdev->config->reset(vdev); |
| vdev->config->del_vqs(vdev); |
| } |
| |
| static int virtscsi_init(struct virtio_device *vdev, |
| struct virtio_scsi *vscsi) |
| { |
| int err; |
| u32 i; |
| u32 num_vqs; |
| vq_callback_t **callbacks; |
| const char **names; |
| struct virtqueue **vqs; |
| struct irq_affinity desc = { .pre_vectors = 2 }; |
| |
| num_vqs = vscsi->num_queues + VIRTIO_SCSI_VQ_BASE; |
| vqs = kmalloc_array(num_vqs, sizeof(struct virtqueue *), GFP_KERNEL); |
| callbacks = kmalloc_array(num_vqs, sizeof(vq_callback_t *), |
| GFP_KERNEL); |
| names = kmalloc_array(num_vqs, sizeof(char *), GFP_KERNEL); |
| |
| if (!callbacks || !vqs || !names) { |
| err = -ENOMEM; |
| goto out; |
| } |
| |
| callbacks[0] = virtscsi_ctrl_done; |
| callbacks[1] = virtscsi_event_done; |
| names[0] = "control"; |
| names[1] = "event"; |
| for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++) { |
| callbacks[i] = virtscsi_req_done; |
| names[i] = "request"; |
| } |
| |
| /* Discover virtqueues and write information to configuration. */ |
| err = virtio_find_vqs(vdev, num_vqs, vqs, callbacks, names, &desc); |
| if (err) |
| goto out; |
| |
| virtscsi_init_vq(&vscsi->ctrl_vq, vqs[0]); |
| virtscsi_init_vq(&vscsi->event_vq, vqs[1]); |
| for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++) |
| virtscsi_init_vq(&vscsi->req_vqs[i - VIRTIO_SCSI_VQ_BASE], |
| vqs[i]); |
| |
| virtscsi_config_set(vdev, cdb_size, VIRTIO_SCSI_CDB_SIZE); |
| virtscsi_config_set(vdev, sense_size, VIRTIO_SCSI_SENSE_SIZE); |
| |
| err = 0; |
| |
| out: |
| kfree(names); |
| kfree(callbacks); |
| kfree(vqs); |
| if (err) |
| virtscsi_remove_vqs(vdev); |
| return err; |
| } |
| |
| static int virtscsi_probe(struct virtio_device *vdev) |
| { |
| struct Scsi_Host *shost; |
| struct virtio_scsi *vscsi; |
| int err; |
| u32 sg_elems, num_targets; |
| u32 cmd_per_lun; |
| u32 num_queues; |
| |
| if (!vdev->config->get) { |
| dev_err(&vdev->dev, "%s failure: config access disabled\n", |
| __func__); |
| return -EINVAL; |
| } |
| |
| /* We need to know how many queues before we allocate. */ |
| num_queues = virtscsi_config_get(vdev, num_queues) ? : 1; |
| num_queues = min_t(unsigned int, nr_cpu_ids, num_queues); |
| |
| num_targets = virtscsi_config_get(vdev, max_target) + 1; |
| |
| shost = scsi_host_alloc(&virtscsi_host_template, |
| struct_size(vscsi, req_vqs, num_queues)); |
| if (!shost) |
| return -ENOMEM; |
| |
| sg_elems = virtscsi_config_get(vdev, seg_max) ?: 1; |
| shost->sg_tablesize = sg_elems; |
| vscsi = shost_priv(shost); |
| vscsi->vdev = vdev; |
| vscsi->num_queues = num_queues; |
| vdev->priv = shost; |
| |
| err = virtscsi_init(vdev, vscsi); |
| if (err) |
| goto virtscsi_init_failed; |
| |
| shost->can_queue = virtqueue_get_vring_size(vscsi->req_vqs[0].vq); |
| |
| cmd_per_lun = virtscsi_config_get(vdev, cmd_per_lun) ?: 1; |
| shost->cmd_per_lun = min_t(u32, cmd_per_lun, shost->can_queue); |
| shost->max_sectors = virtscsi_config_get(vdev, max_sectors) ?: 0xFFFF; |
| |
| /* LUNs > 256 are reported with format 1, so they go in the range |
| * 16640-32767. |
| */ |
| shost->max_lun = virtscsi_config_get(vdev, max_lun) + 1 + 0x4000; |
| shost->max_id = num_targets; |
| shost->max_channel = 0; |
| shost->max_cmd_len = VIRTIO_SCSI_CDB_SIZE; |
| shost->nr_hw_queues = num_queues; |
| |
| #ifdef CONFIG_BLK_DEV_INTEGRITY |
| if (virtio_has_feature(vdev, VIRTIO_SCSI_F_T10_PI)) { |
| int host_prot; |
| |
| host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION | |
| SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION | |
| SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION; |
| |
| scsi_host_set_prot(shost, host_prot); |
| scsi_host_set_guard(shost, SHOST_DIX_GUARD_CRC); |
| } |
| #endif |
| |
| err = scsi_add_host(shost, &vdev->dev); |
| if (err) |
| goto scsi_add_host_failed; |
| |
| virtio_device_ready(vdev); |
| |
| if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) |
| virtscsi_kick_event_all(vscsi); |
| |
| scsi_scan_host(shost); |
| return 0; |
| |
| scsi_add_host_failed: |
| vdev->config->del_vqs(vdev); |
| virtscsi_init_failed: |
| scsi_host_put(shost); |
| return err; |
| } |
| |
| static void virtscsi_remove(struct virtio_device *vdev) |
| { |
| struct Scsi_Host *shost = virtio_scsi_host(vdev); |
| struct virtio_scsi *vscsi = shost_priv(shost); |
| |
| if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) |
| virtscsi_cancel_event_work(vscsi); |
| |
| scsi_remove_host(shost); |
| virtscsi_remove_vqs(vdev); |
| scsi_host_put(shost); |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| static int virtscsi_freeze(struct virtio_device *vdev) |
| { |
| virtscsi_remove_vqs(vdev); |
| return 0; |
| } |
| |
| static int virtscsi_restore(struct virtio_device *vdev) |
| { |
| struct Scsi_Host *sh = virtio_scsi_host(vdev); |
| struct virtio_scsi *vscsi = shost_priv(sh); |
| int err; |
| |
| err = virtscsi_init(vdev, vscsi); |
| if (err) |
| return err; |
| |
| virtio_device_ready(vdev); |
| |
| if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) |
| virtscsi_kick_event_all(vscsi); |
| |
| return err; |
| } |
| #endif |
| |
| static struct virtio_device_id id_table[] = { |
| { VIRTIO_ID_SCSI, VIRTIO_DEV_ANY_ID }, |
| { 0 }, |
| }; |
| |
| static unsigned int features[] = { |
| VIRTIO_SCSI_F_HOTPLUG, |
| VIRTIO_SCSI_F_CHANGE, |
| #ifdef CONFIG_BLK_DEV_INTEGRITY |
| VIRTIO_SCSI_F_T10_PI, |
| #endif |
| }; |
| |
| static struct virtio_driver virtio_scsi_driver = { |
| .feature_table = features, |
| .feature_table_size = ARRAY_SIZE(features), |
| .driver.name = KBUILD_MODNAME, |
| .driver.owner = THIS_MODULE, |
| .id_table = id_table, |
| .probe = virtscsi_probe, |
| #ifdef CONFIG_PM_SLEEP |
| .freeze = virtscsi_freeze, |
| .restore = virtscsi_restore, |
| #endif |
| .remove = virtscsi_remove, |
| }; |
| |
| static int __init init(void) |
| { |
| int ret = -ENOMEM; |
| |
| virtscsi_cmd_cache = KMEM_CACHE(virtio_scsi_cmd, 0); |
| if (!virtscsi_cmd_cache) { |
| pr_err("kmem_cache_create() for virtscsi_cmd_cache failed\n"); |
| goto error; |
| } |
| |
| |
| virtscsi_cmd_pool = |
| mempool_create_slab_pool(VIRTIO_SCSI_MEMPOOL_SZ, |
| virtscsi_cmd_cache); |
| if (!virtscsi_cmd_pool) { |
| pr_err("mempool_create() for virtscsi_cmd_pool failed\n"); |
| goto error; |
| } |
| ret = register_virtio_driver(&virtio_scsi_driver); |
| if (ret < 0) |
| goto error; |
| |
| return 0; |
| |
| error: |
| mempool_destroy(virtscsi_cmd_pool); |
| virtscsi_cmd_pool = NULL; |
| kmem_cache_destroy(virtscsi_cmd_cache); |
| virtscsi_cmd_cache = NULL; |
| return ret; |
| } |
| |
| static void __exit fini(void) |
| { |
| unregister_virtio_driver(&virtio_scsi_driver); |
| mempool_destroy(virtscsi_cmd_pool); |
| kmem_cache_destroy(virtscsi_cmd_cache); |
| } |
| module_init(init); |
| module_exit(fini); |
| |
| MODULE_DEVICE_TABLE(virtio, id_table); |
| MODULE_DESCRIPTION("Virtio SCSI HBA driver"); |
| MODULE_LICENSE("GPL"); |